1. Field of the Invention
The invention relates to a system for recording and reproducing a standard definition (SD) video signal in/from a track on a magnetic record carrier, comprising a recording device which includes:
an input terminal for receiving the SD video signal,
a separation unit having an input coupled to the input terminal, and first and second outputs, which separation unit is arranged for deriving a luminance signal from the SD video signal and presenting this luminance signal at the first output, and for deriving a chrominance signal and presenting same at the second output,
a first signal path comprising an FM modulator,
a second signal path, comprising a mixer stage,
a signal combining unit having first and second inputs coupled to an output of the respective first and second signal paths, and an output,
writing means having an input coupled to the output of the signal combining unit, the system further including a reproducing device which comprises
reading means having an output,
a separation unit having an input coupled to the output of the reading means, first and second outputs, which separation unit is arranged for deriving an FM-modulated luminance signal from the signal read from the track by the reading means and presenting this luminance signal at the first output, and deriving a frequency-converted chrominance signal and presenting same at the second output,
a first signal path including an FM demodulator,
a second signal path including a mixer stage,
a first output terminal coupled to an output of the first signal path, for presenting the demodulated luminance signal, and
a second output terminal coupled to an output of the second signal path, for applying the frequency-shifted chrominance signal, to a recording device and a reproducing device to be used in the system, to a converter means for converting a PAL-PLUS video signal to a video signal that can be recorded on a video tape recorder, and to a converter means for converting a video signal reproduced by a video tape recorder to a PAL-PLUS video signal.
2. Description of the Related Art
The system of the type mentioned in the opening paragraph is known, for example, from Funkschau, No. 6, 1988, pp. 34 and 35. This publication describes how an SD video signal in the form of a PAL video signal is recorded on the record carrier by means of a VHS video tape recorder and an SVHS video tape recorder. Several years ago it was proposed to realize video pictures having a 16:9 aspect ratio in lieu of video pictures having a 4:3 aspect ratio. Pictures having such a 16:9 aspect ratio form a better link to the world of films and to the properties of the human eye. As long as television sets with 4:3 format picture screens are still used, a television broadcast in the 16:9 format will have to be reverse-compatible. Put in other words: for television signals broadcast in the 16:9 format it must also be possible to be reproduced by a television set having a 4:3 picture screen. Such a reverse compatibility can be realized with an extended definition video signal in the form of the PAL-PLUS television signal. For a description of the PAL-PLUS television signal, reference be made to two publications in Funkschau, No. 15, 1990, pp. 49-51 and No. 23, 1990, pp. 46-47 and Fernseh- und Kino-Technik, No. 8, 1989, pp. 407-410 and No. 10, 1989, pp. 522-526.